1. Field of the Invention
The present invention relates to the field of operation system and network storage, and in particular to a virtual machine-based on-demand parallel disaster recovery system and the method thereof.
2. Description of the Relevant Art
Disaster recovery technology can ensure security of data and running of critical businesses without interruption under circumstances of various natural disasters and vandalism in order to create a system with high reliability. According to the positions where data is copied and runs, the current disaster recovery system is divided into the following types: disaster recovery systems based on storage device (storage-based), which is based on special physical storage device, such as MirrorView running on EMC Clariion arrays and SRDF on Symmetrix storage arrays, PPRC of IBM company, and TrueCopy of Hitachi company; disaster recovery systems based on host operation system software (host-based), such as Veritas Volume Replicator (VVR) of Symantec company, which achieves the aim of disaster recovery by copying volume group RVG, and the similar products such as volume shadow copy of Microsoft company; disaster recovery systems based on storage switch (SAN-Based) which realizes backup of data at the storage switching devices, such as SANTap of Cisco and IPStor of FalconStor; disaster recovery systems based on database/applications such as DataGuard of Oracle and remote Q copy of DB2 and so on, which are realized by scanning and recording database log using the copy technology operated on data logic. The advantages of disaster recovery systems based on database/applications include low cost etc, however these systems have strong dependency on database and applications. To sum up, each one of the above present systems has all or part of the following disadvantages: it cannot reserve the running state of applications and can only realize replication on data-level; it depends on special device, so it has a high cost and a small scope of application; it depends on special applications; it takes a long time to copy and to recover data and it wastes much time at the stop state of services.